Derivative Financial Instruments (Notional Amounts, Balance Sheet Location And Estimated Fair Values Of Derivative Financial Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Derivative, Notional Amount	$ 1,525	$ 1,407
Total derivative assets	33	47
Amounts netted	(12)	(21)
Net derivative assets	21	26
Total derivative liabilities	(71)	(29)
Amounts netted	12	21
Net derivative liabilities	(59)	(8)
Hedging Instruments [Member]
Derivative [Line Items]
Derivative, Notional Amount	1,125	825
Hedging Instruments [Member] | Other Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Derivative, Notional Amount	1,125	825
Total derivative assets	3	23
Total derivative liabilities	(60)	(5)
Non-Hedging Instruments [Member]
Derivative [Line Items]
Derivative, Notional Amount	400	582
Total derivative assets	30	24
Total derivative liabilities	(11)	(24)
Non-Hedging Instruments [Member] | Other Noncurrent Assets [Member] | Options [Member]
Derivative [Line Items]
Derivative, Notional Amount	0	100
Total derivative assets	1	0
Total derivative liabilities	0	0
Non-Hedging Instruments [Member] | Equity securities/other assets/other liabilities [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Derivative, Notional Amount	5	119
Total derivative assets	0	0
Total derivative liabilities	0	(5)
Non-Hedging Instruments [Member] | Equity Securities [Member] | Collars [Member]
Derivative [Line Items]
Derivative, Notional Amount	19	19
Total derivative assets	23	21
Total derivative liabilities	(9)	(17)
Non-Hedging Instruments [Member] | Equity Securities [Member] | Futures [Member]
Derivative [Line Items]
Derivative, Notional Amount	358	344
Total derivative assets	2	3
Total derivative liabilities	(2)	$ (2)
Non-Hedging Instruments [Member] | Fixed Maturity Securities [Member] | Embedded Derivative Financial Instruments
Derivative [Line Items]
Derivative, Notional Amount	18
Total derivative assets	4
Total derivative liabilities	$ 0